Fuel pump regulation



Sept 29, 1942 s. MElswlNKEL 2,297,234

FUEL IPUMP REGULATION Filed Jan. 17, 1959 4 Sheets-Shet 1 17 i. C' rag 25 2f, 26V 625' I o v Zigi Bl Y 25 44 2J* 454s l 5 .5243

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. 57 o o o o 29 l/ l f www f5 2'4 ga \25 97 /A/l/f/VO/Pf Y 54m/a /Vf/fM//A//fa Sept. 29, 1942. s. MElswlNKEL FUEL PUMP REGULATION Filed Jan. 17, 1933 4 Sheets-Sheet 5 y 12ga,

,SPt' 29,194; s. MEISWINKEL. y 2,297,234 i ,FUEL PUMP REGULATIoN Filed Jan. 17, 1939 f1 Sheets-Sheet 4 l INVEN TOR. efarfmel /I/ezswinifel 2 l firm NEYS Patented Sept. 29, 1942 FUEL lPUMP REGULATION Samuel Meiswinkel, Gaggenau, Germany; vested in the Alien Property Custodian Application .tammy 11, isaaserai No. 251,321

' In Germany January 28, 1938 (Cl. S-41) 9 Claims.

The invention relates to the regulation of the fuel pumps of internal combustion engines, and has for its object the prevention of excessive speeds of engine revolution, whilst still permitting regulation for the purpose of varying theA feed for various loads upon the engine.' The broader aspects of this invention are covered by myco-pending application Serial No. 251,326, led ofeven date herewith.

In accordance with the invention, this regulation is made possible by a member common to both operations, the 'member being adjusted automatically for limiting. the maximum engine speeds, and at will for lthe regulation of the fuel supply according to they load on the engine. The common member is subject to the influence of a constant and a variable function for the regulation of the fuel supply for the purpose of limit- 'ing the maximum engine speeds, and is adjusted by a manual control, such as the accelerator pedal for the regulation of the fuel in accordance with the load on the engine.

The adjustment of the regulating member at will is effected through the medium of spring means in such fashion that the automatic adjustment for the limitation of the maximum engine speeds can take 'place independently of the regulation of the fuel supply at will in accordance with the load on the engine.

The invention eifects a substantial simpliiication in comparison with known pump regulators,

only narrow inflow passages to the pump pistons are open. Y

A further object is to providev for the deaeration of the suction and pressure spaces/of the fuel pump. Such de-aeration may be effected ina particularly advantageous manner by operating the controlling valve as a pump.A In such operation the valve drawsfuel from the supply passage, when the engine is at rest and supplies it to all the spaces inthe pump and also to the pressure passages leading to the cylinders of the internal combustion engines, so that the air present in the pump and in the passages is got rid of. The valve, for this purpose,

may be operatedv by the accelerator lever, for example from the drivers position, by simple up and down movement of this lever, and the fuel pump may thus loe de-aerated with the vengine at rest. In the supply passage from the fuel reservoir to the pump, there may be a non-return valve to prevent back-flow of the f uel.

With the enginey at rest and the screw connections for the nozzles on the cylinder heads undone, the valve is moved impulsively to and fro by means of the accelerator lever. Upon pullingthis lever, fuel flows in from the supply passage through the recesses of the valve, whereas,

j upon pressing down the lever, the fuel situated wherein separate members are provided, one for has proved appropriate to admit the fuel at the mechanically operated end of the valve. The" valve is readily movable axially in its bore,'by means of a linkage which operates the valve nonpositively by spring means. The actuation of the linkage may be effected either directly from the accelerator pedal or by means of avlever and inthe suction passage and return-flow passage is subjected to pressure. Thus, fuel passes through the controlling valve and is forced vby way of the 'suction passages (or through a relief bore, if a pump piston is standing precisely at the upper dead-centre position) into the pressure spaces of all the pump pistons and thence by way of the pressure valves into the pressure passages. In this fashion, the air present in the pressure spaces and passages is carried along and the pump is effectually de-aerated without the employment ofseparate devices for the purpose. The pumping movement of the valve is continued until fuel emerges from all passages whose nozzle connections have been previously undone, or from the nozzle.

A further object is to divide the common con-A- trol valveso that it comprises two valves, sliding one in the other, with inter-related actions. It has proved that a regulating member adjustable within wide limits is advantageous for the regulation at will of the fuel supply, whereas a member .adjustable within narrower limits is desirable cam. The lspring arrangement may be such-that in the idle-running position, a stronger spring always forces the valve into a position in which lfor the lautomatic regulation for the purpose of preventing excessive speed. The twoivalves sliding one in the other fulfil these requirements.

the cuter valve, for example, possessing ,comparai bores 2s ena recesses 21 which, after tile exetively wide or long control portings and being actuated by the accelerator lever. The second sliding within the first has comparatively short control portings. During normal operation. the second valve is pressed by a spring against a stop in the first valve, so that the full passage cross section from the supply to the control portings of the outer valve is available for the fuel. The inner valve for the automatic regulation of the maximum engine speed is provided with a throttling member which connects the pump inflow passage to the pump relief passage. If the dynamic pressure in front of the throttling member exceeds the spring pressure with which the inner valve is pressed against the said stop then a constriction takes place of the passages to the outer valve and, consequently, to the spaces of the pump pistons. Thus, less fuel is supplied to the cylinders of the internal combustion engine and running away of the said engine is prevented.

By the division of the regulating member into' two valves sliding one'in the other and dependent one on the other, the requirements of operation in regard to wide regulation of the fuel supply at will and quickly acting regulation for the automatic limitation of the maximum speed can be taken into account.

Embodiments of the invention by way of example are illustrated diagrammatically in thev annexeddrawings, wherein:

Figure 1 is a cross section through a fuel pump having an improved regulator, the section being taken on the line A-A of Figure .2;

l Figure 2 is a longitudinal section taken on the line B-B of Figure 1;

Figure 3 is a horizontal section taken on the line C-C of Figure -.1;

Figure 4 is an enlarged perspective view of an individual part of theoontrolling valve seen in Figures 1 to 3;

Figure 4a is a transverse cross-sectional view along the line'A of Fig. 4, showing the relationship of the valve part to the surounding pump casing;

Figure 4b isa similar transverse cross-sectional view along: the line B of Fig. 4;

Figure 5 is a cross section of a modification;

Figure' 6 is a plan section similar to Figure 3, but illustrating a further modification;

lFigure 7 is similar to Figure 6 but shows the parts in a different position;

Figure is a plan section illustrating yet another modiflcation;

Figure 9 is a longitudinal section of a fuel pump having a divided form of regulator the section .being taken on the line E-EL (Figure 10);

Figure 10 is al cross section taken on the line D-D (Figure 9); and- Figure 11 is a plan section taken on the line F-f-F of Figure 10.

In Figures 1 to 3 the fuel pump Il has an in flow or inlet passage I3 and a relief or return passage I1, these two passages being in communication with each other through a' passage I3 and a restricted orifice or throttling bore 43 hereinafter'described. In the inflow passage I3' there is a regulator valve I9 which is axially adjustpassage I1. The pump pistons are provided-with.

cution of a certain piston stroke, allow the excess quantity of fuel to ilow into the relief passage |1. The anti-friction rollers of the pistons 2| are pressed Lby the springs 66 against the cams 23. Thefuel is admitted at 28 past a nonreturn valve (not shown) which prevents back flow into the tank or reservoir. The valve I9 has an extension 29 upon which a sliding block 30' is loosely mounted, this block being pressed by a spring 43 against stop nuts 3| on the extension 29. A yoke 32, which is connected to the accelerator pedal lever (not shown) by way of the linkage 42, engages with the sliding block`3l. The spring 43 bears at its" inner end.y against the valve I9.

In order to compensate for the inaccuracies of machining, the controlling valve comprises, as illustrated in Figure 2, individual sleeve parts 33,

34, 35, 3S which are formed with shaped recesses 31. For example, Figure 4 shows one of these parts as being f ormed' with a controlling recess of a depth increasing from the left to the right and from front to rear. Thus, for example, if the canal 24 is positioned opposite the recess 31 in the plane A, there will be produced a throttling cross-section .'ci, as seen in Fig. 4a. While if the sleeve part 33 is shifted so that the canal 24 contacts the recess 31 in the plane D, a larger throttling cross-section xa will be formed, as is seen in Fig. 4b. In any event, the recess is shallow at one end and deep at the other. Each recess has a port passing through the sleeve as shown. The yindividual parts 33 to 33 are arranged upon a connecting tube 39 which has the throttling orice 43 aforesaid at its end. yThe fuel flowing to the valve I9 passes through ports orpassages 3l in 'the tube 39 and through the shaped recesses to the cylinders 20 by way of the passages 24. By turning the sleeve parts 33, 34, 35, 36 upon the tube 39, the cross sections of the passages o r openings leading to the pump cylinders 23 can be varied when the parts are assembled and the inaccuracies of manufacture thus compensated for. Figure 5 illustrates a modification wherein the inflow to the cylinders 20 can be varied by adjustable screws 4I which extend into the passages 24. I n this case, the controlling valve I9 is made in one piece with annular shaped recessesextending around it and the sleeve parts are dispensed with. As will be observed, the shaped recesses of the valve work in conjunction with the port openings of the passages 24.

vThe manner of operation is asfollows: Movev ment is transmitted from the accelerator pedal,

not shown,` tothe rod 42 and fork 32, so that the sliding block 30, through the spring 43, imparts axial movement to the valve I3. For acceleration o f the engine, the valve I3 is'moved towards the left in Figure 2, whereby the recesses 31 open the passages 24 leading to the pump cylinders 2l as far as is necessary. Upon releasing the' ac-l celeratoi pedal, the valve i3 'is displaced towardsl the right under the action of a pedal spring, not

shown, theA block 33 operating ony the valve through the stop nuts 3|. By this movement, the

inflow cross-sections arereduced so that a small-v er quantity of fuel flows to the cylinders. If, during the regulating operation by the accelerator pedal, the ultimate speed of the engine becomes too high, then the controlling valve |3 is displaced to the right. A back pressure builds up against the inner end of the valve. Under the action of this pressure at the nozzle 40, the valve is moved to the right and the nuts QI, separate from the sliding block 30, the lspring 43 being at the same time compressed. This rightward movement of the valve effects, of course, a reduction of the fuel supply. The movement of the duced, whereas the valve opens the maximumcross-section in its left hand end position.

The above-described regulating device will effect the delivery of the fuel pump in a manner which will bey obvious to those skilled in this art. When the piston 2I moves downwardly from its uppermost position, after the return passage 25 has been closed. a vacuum will be created in the cylinder bore 20. If it is assumed that the valve I9 is displaced toward the left as seen in Fig. 2. thereby presenting va large opening from the supply I6 to the passage 24, as soon as the piston opens the ,passage 24, the fuel will rush into the cylinder -bore 20, due to the effect of the vacuum and substantially fill this space. If, however, the valve I9 is moved toward the right, as seen in Fig. 2, the opening between the supply conduit I6 and the passage 24 will be substantially throttled, so that the vacuum produced in the cylinder space by descent of the piston 2| willdraw in much less fuel than previously before the piston again rises. Therefore, during the up stroke of the piston 2 I, the total amount of fuel drawn into the cylinder space 20 will be so much less that the total delivery of the pump is substantially. reduced. v

In Figures 6 and '7, lports 46 lead from the interior of the tubular valve I9 to the shaped recesses 41 which are cut in the periphery of the valve and control the bores 24 leading to the pump pistons. The stroke of the valve I9 Vto the left may be limited by an adjustable stop 44. The fuel is admitted through openings, I into the interior of the valve and through the port 45 and recesses 41 to the passagesl 24 leading to the pump cylinders 20. -Y

The housing I5 carries on the. right-hand side,

, an extension for receiving a plug 95 possessing a stuillng box 8`6-with packing 45 through which a rod 49-is carried outwardly. This rod 49 has The operation of the arrangement in Figures 6 and 'I is as follows:

For theA acceleration of the engine at will, the cam 55 is brought by the lever 56 into the position illustrated in Figure 6 and the rod 49 is therebyforced to the left, the spring 53 being compressed at the same'time. Under the action of the spring 52, the valve I9 is likewise displaced to the left so that the shaped recesses- 41 open the largest cross-section to the fuel inlet passages 24 and the pump pistons 2l supply a corresponding quantity of fuel to the cylinders of the engine. If the output of the engine is to be reduced, the spring 51, after release of the accelerator rod, brings the lever 56 and, with it, the cam 55 into4 a position in which the rod 49 is 4forced to the right under the action of the spring 53. 'I'he valve I9 is thus also moved rightwardly so that the cross-sections of openings leading tov de-aerated with the engine at rest, the valve I9 is moved to and fro by the accelerator linkage 32, 42, seen in Figure 8. The, fuel is drawn in through the connection 62 which encloses anonreturn valve 54 loaded by a spring 53. Upon drawing the valve to the right, fuel flows in from the supply. passage. whereas upon pressing the valve tothe left the fuel situated in the suction and return passages I6, lil,- I1 is subjected to pressure such that the said fuel passes into the pressure'spaces of the cylinders A2i) of all the sages are completely free from air.

a head 50 which is moved rightwardly against 4 the the valve I 9, theV rod I9 being passed freely by, for example, a flexible diaphragm 13 which is secured be'tween the socket 14 and plug 15.

lation of the maximum idle-running speed.v A

draw the lever 56 and cam 55 into the idle-running or stop position illustrated in Figure 7. A.' housing 59, for example. serves for the mounting of the cam shaft5l. C

Within the scope of the invention, it is immaterial whether the valve I9 is operated by the accelerator pedal or `lever from the drivers position or by any other suitable device.

In `the divided valve construction seen in Figures `9 to ll, the regulator valve comprises an' inner tubular part 11 and an outer tubular part 51. The latter, which is provided for the regulation of the speed at will and is furnished with ports 54 opening into shaped recesses 69, slides in the inflow passage I5. 'I'he valve part 51 vis provided at the one-end with a screw-in tubular plug 10 and at the other end with a screw-in plug 1I. Connected to lthe latter is a ball pivot 12 with which the linkage of the accelerator lever engages for the movement of the valve part 61 at will. I'he valve is sealed towards the outside part 511s for the automatic regulation of the maximum engine speed., This valve part 11 communicates with the relief passage I1 through va throttle opening 1l in a plug which is inserted in the inner end of the tubular part 11. The

last-named Vis pressed by a spring 19 against the tubular plug 1l which acts as a stop in the outer valve part I1: A connecting duct s0 between the overflow passage I1 and inlet bore Il is held by the screwed-in part 8| which encloses an adjustable stop 82 for the valve part 01. The valve part 11 is provided with ports 83 and shaped recesses I4 which overlap the ports 68 of the valve part 61 in normal operation, that is in the left' hand end position of the valve.

The operation of the arrangement in Figures 9 to 1l is as follows:

For the variation at will of the output and speed of the internal combustion engine, the outer valve part 61 is displaced by the accelerator lever to the right or left and the passage crosssections from the inflow i8 to the passages 24 and pump spaces 2l are thus varied so that more or less liquid passes into the cylinders of the internal combustion engine. 'I'he valve part 11 accompanies the valve 61 in these movements as long as no dynamic pressure `arises from the overflow in front of the throttling bore 1I. If, however, this dynamic pressure overcomes the force of the spring 19, then the valve 11 ,is displaced vto the right against this spring force and the cross sectionsof the openings uncovered by the. recesses and leading to the ports 6I are thus reduced, so that less fuel can flow through. By this means, the allowable maximum speed of the internal combustion engine cannot be exceeded. The recesses u on the valve part 11 are shorter than the recesses 6! on the valve part I1 so that reduction of the passage. cross-sections takes place for a slight movement of the valve 11 and running away of the internal combustion engine is prevented by the rapid closure of the fuel supply means. The longer' recesses of the valve part 61, however, afford the more gradual control which'is required for accelerator-"pedal adiustments.

In connection with the form of regulator which is made in two relatively adjustable parts to take care of machining inaccuracies, it is/to be noted that lthe sleeve maybe .assembled upon the connecting tube in any suitable -manner known to the art. If desired, the adjustment ycan be made during assembly, the sleeve being forced onto the central tubedn the ,desired position inv which case no 'particular relative holding means will be necessary. For. a less rigid, but more flexible correction. the sleeve may be slipped on the tube and adjusted by a suitable threaded interconnection or by pins. It is to be pointed out,

.let passages having an interconnecting throttling bore for establishing a pressure differential between said inlet 'and return passages, and manual means for operating said regulating means.

2. In a uid pump including at least one pump cylinder space having a piston therein, an inlet passage for said cylinder space, a canal in said pump. opening into said inlet passage vand said l,cylinder space for injecting fluid to the latter from said inlet passage2 a return passage leading from said cylinder space to said inlet passage an adjustable plug extending into said canal for varying its effective cross-sectional area, and an axially shiftable slide valve movable in one direction or the other in accordance with the dfference in pressure within said inlet and return passages for varying the flow of fluid from said inlet passage to said canal, said slide valve including means intermediate said return and inlet passages having an interconnecting throttling bore for establishing a pressure diiIerential between said inlet and return passages.

3. In a fluid pump including at least one pump cylinder space having a piston therein, an inlet passage connected to said cylinder space, a delivery passage leading from said cylinder space, a

return passage leading from said cylinder space,

to said inlet passage, regulating means for varying theamount of fuel supply t0 said cylinder space, said regulating means including means intermediate said return andinlet passages having an interconnecting throttling bore for establishing a pressure diiIerential between said-inlet and return passages, an extension on said regulating means having a stop at the end thereof, a slide on said. extension, spring means intermediate said regulating means land said slide for urging the latter against said stop, a control arm for moving said slide against said spring for actuation of said regulating means in one direction, and against said stop for actuation of said regulating means in the opposite direction, said regulating means also being subjected to the pressure within said return passage for-move ment thereof against said spring, independently of the position of said control arm.

however, that the particular means forobtaining the adjustment is without importance with respect to the principles of the present invention. It will accordingly be seen that I have provided a construction which will satisfy the obiects enumerated above, and while I have shown the in' ventlon in certain physical embodiments, it is to be understood that modifications of the structure shown may be made by thoseskillcd infthis art without departing from my invention as expressed in the claims which follow.

1.l In a fluid pump including atleast one -pump cylinder space having a piston therein, an

inlet passage connected tothe cylinder space, a delivery passageleading from the cylinder space.' a return'passage leadinsfrom said cylinder space s to said inlet passage, lregulating means movable in o'ne direction or the other inA accordance with v the difference inpressure in vsjaitl inlet passages for varying the amount o f fluid supplied to said cylinder space, said,regula'tinlililetlll *turn and inlet passages having an interconnect- 4. In a iluid pump including at least one pump cylinder space having a piston therein, an inlet passage connected to said cylinder space, a delivery passage leading from said cylinder space,y a return e leading from said cylinder space to saldi inlet e, a throttle valve axially shiftable in said inlet passage for controlling the amount of fluid to said cylinder space, said throttle valve including means intermediate said reingv throttling bore for establishing a. pressure differential between said niiet and return passages, a stumng box closing one end of said inlet passage, first spring means intermediate said stuiling box and throttle valve for urging the latter inone direction, a rod extending through said stuiling box,'having a head slidably engaging said on its other end, second spring means intermedis ate said stufllng box and said abutment plate for ,mcmqinsfnfem intermediates@ malin-'16 urging engagement of said head with said valve ,for movement of the latter against said nrst spring,.and an adjustable cam in contact with said` abutment plate for moving the same and thereby initiating axial shifting of said valve.

5. Ihe combination according to claim 4. in which said valve is subjected to the pressure within said return passage for movement in a directa oppositely to the force of said rst sminne combination ,according to claim 4, in Wh; the second spring is stronger than the rst v sg'n'a fuel pump including at least one pump der space having a piston therein, an inlet ysage having a, canal opening into said cylinyf' space, a hollow cylindrical slide valve mount- ,f for reciprocatory movement within said inlet tissage for controlling the flow of uid through id canal, said slide valve being formed of an ynner hollow cylinder having a passage there- /through and an outer hollow sleeve rotatably ad- /justable upon said inner cylinder and having a `passage interconnecting the passage of said inner cylinder with the canal insaid supply conduit, means vfor moving said slide valve, and a delivery passage leading from said cylinder space. A 8. In a fuel pump including at least one pump cylinder space having a piston therein, an inlet passage having a canal opening into said cylinder space, a hollow cylindrical slide valve mounted for reciprocatory movement within said inlet passage for controlling the iiow of fluid through said canal, said slide valve comprising an inner hollow cylinder vhaving a passage therethrough and an outer hollow cylinder relatively longitudinally slidable upon said inner cylinder and having a passage interconnecting the passage ofl said inner cylinder with the canal in said inlet passage,

' a return passage in said pump leading from said cylinder space to said inlet passage, a delivery passage leading from said cylinder space, and

means having a throttling bore in one end of said inner cylinder for establishing a pressure differential between said return and inlet passages, acting to move said inner cylinder relatively to said outer cylinder.

9. In an injection internal combustion engine,

SAMUEL MEISWINKEL. 

